1. Field of the Invention
This invention relates to steering apparatus for a vehicle and, more particularly, to a self-aligning support structure for a rod and cylinder of a power steering unit for use in a lift truck or the like.
2. Description of the Prior Art
Steering apparatus for certain vehicles, such as lift trucks and the like, is arranged to turn the vehicle by operating on the rear wheels of the vehicle which are beneath the counterweighted end of the vehicle. In this way, there is an unusually heavy load on the steering wheels necessitating different steering actuating apparatus than normally used. One prior system, as shown in U.S. Pat. No. 3,480,100 to G. L. Gaulke, provides for a double ended actuator unit rigidly mounted on the frame of the steering axle, said frame being resiliently mounted by rubber cushions to the body of the vehicle. Due to the rigid mounting on the double ended rod and cylinder, any misalignment between the rod of the actuator unit and the steering arm of the steering knuckle can cause the system to bind or to wear excessively.
In another prior art device, as shown in U.S. Pat. No. 3,768,585 to N. J. Matteo, a power steering unit is shown on a lift truck wherein a double ended actuator unit is supported on bearings seated in elongate slots in the frame of the steering axle so as to permit the cylinder to move to a limited extent along the axis of the slots as the wheels are turned. Although this system does provide for some horizontal adjustment for misalignment between the rod of the actuator unit and the steering arm of the steering knuckle, it only provides for adjustments for misalignment in the horizontal plane and does not provide for adjustments for misalignment in the vertical plane where most adjustments are needed.